učinak propilen-glikola i glicerola na metabolizam ugljikohidrata i masti u kunića - kratko priopćenje

This study examined the effects of glycogenic precursors (propylene glycol and glycerol) on lipid and carbohydrate metabolism of rabbit does fed a restricted diet. The study included 48 females of the Hyplus genetic line, divided into primiparous and multiparous groups. On the 4th day of the restricted diet, the rabbits were orally administered propylene glycol (PG) or glycerol (G), 2 mL/kg body weight0.75. Blood samples were collected immediately prior to administration of the glycogenic precursors and 30, 60, 90, 180, and 360 minutes thereafter. Serum concentrations of glucose, non-esterified fatty acids (NEFA), and β-hydroxybutyric acid were determined. Following the use of both glycogenic precursors, glucose concentration increased after 30 min., which was maintained until the end of the experiment. A significant (P<0.01) decrease in NEFA occurred 120 min after PG was given to primiparous and multiparous does, and remained low up to 360 min after administration. For glycerol, the decrease in NEFA occurred later after 360 min. The mean glucose concentration for the whole period was lower in multiparous females, and higher in primiparous ones. We revealed that both propylene glycol and glycerol showed the evident effect of lipolysis inhibition and gluconeogenesis stimulation, which can be used in practice (e.g. lactation, reproduction).U ovom je radu istraživan učinak glikogenskih pretskazatelja (propilen-glikola i glicerola) na metabolizam masti i ugljikohidrata u kunića hranjenih restriktivnim obrocima. U istraživanje je uključeno 48 ženki genetičke linije Hyplus, podijeljenih u skupine s obzirom na to jesu li primipare ili multipare. Četvrti dan restriktivne hranidbe kunićima je oralno primijenjen propilen-glikol (PG) ili glicerol (G) u dozi od 2 mL/kg tjelesne mase0,75. Uzorci krvi prikupljeni su neposredno prije primjene glikogenskih pretskazatelja te 30, 60, 90, 180 i 360 minuta poslije njihove primjene. Određene su serumske koncentracije glukoze, neesterificiranih masnih kiselina (NEFA) i beta-hidroksimaslačne kiseline. Primjenom obaju glikogenskih pretskazatelja, koncentracija glukoze porasla je nakon 30 minuta i ta se vrijednost zadržala do kraja istraživanja. znakovito smanjenje (P < 0,01) NEFA-e bilo je 120 minuta nakon što je PG primjenjen kod primipara i multipara, te je ostao nizak do 360 minuta nakon primjene. Davanjem glicerola vrijednost NEFA-e smanjila se poslije 360 minuta. Srednja vrijednost glukoze u cijelom tom razdoblju bila je niža u multipara, a viša u primipara. Pokazalo se da i propilen-glikol i glicerol imaju učinak lipolitičke inhibicije i stimulacije glukoneogeneze, što se može primijeniti u praksi, primjerice tijekom laktacije i reprodukcije kunića

Magnetic properties of moir\'e quantum dot arrays

We investigate magnetic properties of quantum dot arrays of moir\'e triangular superlattices. Starting from a reciprocal space model, we use the projection technique to obtain maximally localized Wannier functions and determine generalized Hubbard model parameters. The many-body Hamiltonian is solved using the exact diagonalization method as a function of the number of electrons in differently shaped quantum dots arrays. Finite spin polarization is observed within a wide range of filling factors for small twist angles and sufficiently strong interactions in most of the studied structures. The prospect for a magnetization controlled by applying a displacement field is presented. In the vicinity of half-filling, signatures of Nagaoka ferromagnetism in moir\'e materials are seen, which we demonstrate by comparing results with the corresponding on-site Hubbard model.Comment: 8 pages, 9 figure

Utjecaj različitog opterećenja treningom na neke pokazatelje u krvi konja za preponsko jahanje

The aim of the study was to assess the changes in the hematology and blood chemistry of jumping horses under the different workload trainings. Group A was trained with a rider and without additional exercises. Group B had an additional daily training session on the treadmill. Blood samples were taken at rest, before exercise and 24 hours after the jumping competition (at the beginning of the season, in the middle and at the end). Regardless of the type of training intensity level and workout load, the post-exercise studies showed an increase in RBC, HGB and HCT. In Group B, there was increase (P<0.05) of resting parameters RBC and HGB between the start of the season and in the middle. During the study there was an increase in AST, LDH, CK in both groups after training. Horses from Group B, subjected to additional training at the end of the season, had lower activity in the resting parameters of AST, LDH and CK than horses from group A. In group B the resting value of LA was lower in the middle and at the end of the sports season, in comparison to group A. The research indicated the desirability of introducing additional stimulation of movement in horses between the relevant trainings involving a rider.Cilj istraživanja bio je procijeniti promjene u hematološkim i biokemijskim pokazateljima kod konja za preponsko jahanje. Konji su podvrgnuti različitim opterećenjima treningom: skupina A trenirala je s jahačem i bez dodatnih vježbi, skupina B imala je dodatan dnevni trening na pokretnoj traci za trčanje. Uzorci krvi uzeti su u mirovanju, prije vježbanja i 24 sata nakon natjecanja u preponskom jahanju (početak, sredina i završetak sezone). Bez obzira na vrstu treninga te razinu njegova intenziteta i opterećenja, nakon vježbanja ustanovljeno je povećanje broja eritrocita (RBC), koncentracije hemoglobina (HGB) i hematokrita (HCT). U skupini B došlo je do povećanja (P<0,05) pokazatelja u mirovanju: RBC i HGB između početka sezone i sredine sezone. Tijekom istraživanja u obje je skupine nakon treninga došlo do povećanja aspartat-aminotransferaze (AST), laktat dehidrogenaze (LDH) i kreatin kinaze (CK). Konji iz skupine B, podvrgnuti dodatnom treningu, na kraju sezone imali su nižu aktivnost pokazatelja AST, LDH i CK u mirovanju od konja iz skupine A. U skupini B pokazatelji mliječne kiseline (LA) u mirovanju bili su niži u sredini i na kraju sportske sezone u usporedbi sa skupinom A. Istraživanje upućuje na poželjnu praksu kojom se između treninga, koji uključuju jahača, uvodi dodatna stimulacija kretanja konja

The effects of heat stress on the behaviour of dairy cows – a review

Heat stress in livestock is a function of macro- A nd microclimatic factors, their duration and intensity, the environments where they occur and the biological characteristics of the animal. Due to intense metabolic processes, high-producing dairy cows are highly vulnerable to the effects of heat stress. Disturbances in their thermoregulatory capability are reflected by behavioural, physiological and production changes. Expression of thermoregulatory behaviour such as reduction of activity and feed intake, searching for cooler places or disturbances in reproductive behaviours may be very important indicators of animal welfare. Especially maintenance of standing or lying position in dairy cattle may be a valuable marker of the negative environmental impact. Highly mechanized farms with large numbers of animals have the informatic system that can detect alterations automatically, while small family farms cannot afford this type of equipment. Therefore, observing and analysing behavioural changes to achieve a greater understanding of heat stress issue may be a key factor for developing the effective strategies to minimize the effects of heat stress in cattle. The aim of this review is to present the state of knowledge, over the last years, regarding behavioural changes in dairy cows (Bos taurus) exposed to heat stress conditions and discuss some herd management strategies providing mitigation of the overheat consequences